[thirdparty/git.git] / quote.c

#include "cache.h"
#include "quote.h"

int quote_path_fully = 1;

/* Help to copy the thing properly quoted for the shell safety.
 * any single quote is replaced with '\'', any exclamation point
 * is replaced with '\!', and the whole thing is enclosed in a
 *
 * E.g.
 *  original     sq_quote     result
 *  name     ==> name      ==> 'name'
 *  a b      ==> a b       ==> 'a b'
 *  a'b      ==> a'\''b    ==> 'a'\''b'
 *  a!b      ==> a'\!'b    ==> 'a'\!'b'
 */
static inline int need_bs_quote(char c)
{
	return (c == '\'' || c == '!');
}

void sq_quote_buf(struct strbuf *dst, const char *src)
{
	char *to_free = NULL;

	if (dst->buf == src)
		to_free = strbuf_detach(dst, NULL);

	strbuf_addch(dst, '\'');
	while (*src) {
		size_t len = strcspn(src, "'!");
		strbuf_add(dst, src, len);
		src += len;
		while (need_bs_quote(*src)) {
			strbuf_addstr(dst, "'\\");
			strbuf_addch(dst, *src++);
			strbuf_addch(dst, '\'');
		}
	}
	strbuf_addch(dst, '\'');
	free(to_free);
}

void sq_quote_print(FILE *stream, const char *src)
{
	char c;

	fputc('\'', stream);
	while ((c = *src++)) {
		if (need_bs_quote(c)) {
			fputs("'\\", stream);
			fputc(c, stream);
			fputc('\'', stream);
		} else {
			fputc(c, stream);
		}
	}
	fputc('\'', stream);
}

void sq_quote_argv(struct strbuf *dst, const char** argv, size_t maxlen)
{
	int i;

	/* Copy into destination buffer. */
	strbuf_grow(dst, 255);
	for (i = 0; argv[i]; ++i) {
		strbuf_addch(dst, ' ');
		sq_quote_buf(dst, argv[i]);
		if (maxlen && dst->len > maxlen)
			die("Too many or long arguments");
	}
}

char *sq_dequote_step(char *arg, char **next)
{
	char *dst = arg;
	char *src = arg;
	char c;

	if (*src != '\'')
		return NULL;
	for (;;) {
		c = *++src;
		if (!c)
			return NULL;
		if (c != '\'') {
			*dst++ = c;
			continue;
		}
		/* We stepped out of sq */
		switch (*++src) {
		case '\0':
			*dst = 0;
			if (next)
				*next = NULL;
			return arg;
		case '\\':
			c = *++src;
			if (need_bs_quote(c) && *++src == '\'') {
				*dst++ = c;
				continue;
			}
		/* Fallthrough */
		default:
			if (!next || !isspace(*src))
				return NULL;
			do {
				c = *++src;
			} while (isspace(c));
			*dst = 0;
			*next = src;
			return arg;
		}
	}
}

char *sq_dequote(char *arg)
{
	return sq_dequote_step(arg, NULL);
}

/* 1 means: quote as octal
 * 0 means: quote as octal if (quote_path_fully)
 * -1 means: never quote
 * c: quote as "\\c"
 */
#define X8(x)   x, x, x, x, x, x, x, x
#define X16(x)  X8(x), X8(x)
static signed char const sq_lookup[256] = {
	/*           0    1    2    3    4    5    6    7 */
	/* 0x00 */   1,   1,   1,   1,   1,   1,   1, 'a',
	/* 0x08 */ 'b', 't', 'n', 'v', 'f', 'r',   1,   1,
	/* 0x10 */ X16(1),
	/* 0x20 */  -1,  -1, '"',  -1,  -1,  -1,  -1,  -1,
	/* 0x28 */ X16(-1), X16(-1), X16(-1),
	/* 0x58 */  -1,  -1,  -1,  -1,'\\',  -1,  -1,  -1,
	/* 0x60 */ X16(-1), X8(-1),
	/* 0x78 */  -1,  -1,  -1,  -1,  -1,  -1,  -1,   1,
	/* 0x80 */ /* set to 0 */
};

static inline int sq_must_quote(char c)
{
	return sq_lookup[(unsigned char)c] + quote_path_fully > 0;
}

/* returns the longest prefix not needing a quote up to maxlen if positive.
   This stops at the first \0 because it's marked as a character needing an
   escape */
static size_t next_quote_pos(const char *s, ssize_t maxlen)
{
	size_t len;
	if (maxlen < 0) {
		for (len = 0; !sq_must_quote(s[len]); len++);
	} else {
		for (len = 0; len < maxlen && !sq_must_quote(s[len]); len++);
	}
	return len;
}

/*
 * C-style name quoting.
 *
 * (1) if sb and fp are both NULL, inspect the input name and counts the
 *     number of bytes that are needed to hold c_style quoted version of name,
 *     counting the double quotes around it but not terminating NUL, and
 *     returns it.
 *     However, if name does not need c_style quoting, it returns 0.
 *
 * (2) if sb or fp are not NULL, it emits the c_style quoted version
 *     of name, enclosed with double quotes if asked and needed only.
 *     Return value is the same as in (1).
 */
static size_t quote_c_style_counted(const char *name, ssize_t maxlen,
                                    struct strbuf *sb, FILE *fp, int no_dq)
{
#undef EMIT
#define EMIT(c)                                 \
	do {                                        \
		if (sb) strbuf_addch(sb, (c));          \
		if (fp) fputc((c), fp);                 \
		count++;                                \
	} while (0)
#define EMITBUF(s, l)                           \
	do {                                        \
		if (sb) strbuf_add(sb, (s), (l));       \
		if (fp) fwrite((s), (l), 1, fp);        \
		count += (l);                           \
	} while (0)

	size_t len, count = 0;
	const char *p = name;

	for (;;) {
		int ch;

		len = next_quote_pos(p, maxlen);
		if (len == maxlen || !p[len])
			break;

		if (!no_dq && p == name)
			EMIT('"');

		EMITBUF(p, len);
		EMIT('\\');
		p += len;
		ch = (unsigned char)*p++;
		if (sq_lookup[ch] >= ' ') {
			EMIT(sq_lookup[ch]);
		} else {
			EMIT(((ch >> 6) & 03) + '0');
			EMIT(((ch >> 3) & 07) + '0');
			EMIT(((ch >> 0) & 07) + '0');
		}
	}

	EMITBUF(p, len);
	if (p == name)   /* no ending quote needed */
		return 0;

	if (!no_dq)
		EMIT('"');
	return count;
}

size_t quote_c_style(const char *name, struct strbuf *sb, FILE *fp, int nodq)
{
	return quote_c_style_counted(name, -1, sb, fp, nodq);
}

void quote_two_c_style(struct strbuf *sb, const char *prefix, const char *path, int nodq)
{
	if (quote_c_style(prefix, NULL, NULL, 0) ||
	    quote_c_style(path, NULL, NULL, 0)) {
		if (!nodq)
			strbuf_addch(sb, '"');
		quote_c_style(prefix, sb, NULL, 1);
		quote_c_style(path, sb, NULL, 1);
		if (!nodq)
			strbuf_addch(sb, '"');
	} else {
		strbuf_addstr(sb, prefix);
		strbuf_addstr(sb, path);
	}
}

void write_name_quoted(const char *name, FILE *fp, int terminator)
{
	if (terminator) {
		quote_c_style(name, NULL, fp, 0);
	} else {
		fputs(name, fp);
	}
	fputc(terminator, fp);
}

extern void write_name_quotedpfx(const char *pfx, size_t pfxlen,
                                 const char *name, FILE *fp, int terminator)
{
	int needquote = 0;

	if (terminator) {
		needquote = next_quote_pos(pfx, pfxlen) < pfxlen
			|| name[next_quote_pos(name, -1)];
	}
	if (needquote) {
		fputc('"', fp);
		quote_c_style_counted(pfx, pfxlen, NULL, fp, 1);
		quote_c_style(name, NULL, fp, 1);
		fputc('"', fp);
	} else {
		fwrite(pfx, pfxlen, 1, fp);
		fputs(name, fp);
	}
	fputc(terminator, fp);
}

/* quote path as relative to the given prefix */
char *quote_path_relative(const char *in, int len,
			  struct strbuf *out, const char *prefix)
{
	int needquote;

	if (len < 0)
		len = strlen(in);

	/* "../" prefix itself does not need quoting, but "in" might. */
	needquote = next_quote_pos(in, len) < len;
	strbuf_setlen(out, 0);
	strbuf_grow(out, len);

	if (needquote)
		strbuf_addch(out, '"');
	if (prefix) {
		int off = 0;
		while (prefix[off] && off < len && prefix[off] == in[off])
			if (prefix[off] == '/') {
				prefix += off + 1;
				in += off + 1;
				len -= off + 1;
				off = 0;
			} else
				off++;

		for (; *prefix; prefix++)
			if (*prefix == '/')
				strbuf_addstr(out, "../");
	}

	quote_c_style_counted (in, len, out, NULL, 1);

	if (needquote)
		strbuf_addch(out, '"');
	if (!out->len)
		strbuf_addstr(out, "./");

	return out->buf;
}

/*
 * C-style name unquoting.
 *
 * Quoted should point at the opening double quote.
 * + Returns 0 if it was able to unquote the string properly, and appends the
 *   result in the strbuf `sb'.
 * + Returns -1 in case of error, and doesn't touch the strbuf. Though note
 *   that this function will allocate memory in the strbuf, so calling
 *   strbuf_release is mandatory whichever result unquote_c_style returns.
 *
 * Updates endp pointer to point at one past the ending double quote if given.
 */
int unquote_c_style(struct strbuf *sb, const char *quoted, const char **endp)
{
	size_t oldlen = sb->len, len;
	int ch, ac;

	if (*quoted++ != '"')
		return -1;

	for (;;) {
		len = strcspn(quoted, "\"\\");
		strbuf_add(sb, quoted, len);
		quoted += len;

		switch (*quoted++) {
		  case '"':
			if (endp)
				*endp = quoted;
			return 0;
		  case '\\':
			break;
		  default:
			goto error;
		}

		switch ((ch = *quoted++)) {
		case 'a': ch = '\a'; break;
		case 'b': ch = '\b'; break;
		case 'f': ch = '\f'; break;
		case 'n': ch = '\n'; break;
		case 'r': ch = '\r'; break;
		case 't': ch = '\t'; break;
		case 'v': ch = '\v'; break;

		case '\\': case '"':
			break; /* verbatim */

		/* octal values with first digit over 4 overflow */
		case '0': case '1': case '2': case '3':
					ac = ((ch - '0') << 6);
			if ((ch = *quoted++) < '0' || '7' < ch)
				goto error;
					ac |= ((ch - '0') << 3);
			if ((ch = *quoted++) < '0' || '7' < ch)
				goto error;
					ac |= (ch - '0');
					ch = ac;
					break;
				default:
			goto error;
			}
		strbuf_addch(sb, ch);
		}

  error:
	strbuf_setlen(sb, oldlen);
	return -1;
}

/* quoting as a string literal for other languages */

void perl_quote_print(FILE *stream, const char *src)
{
	const char sq = '\'';
	const char bq = '\\';
	char c;

	fputc(sq, stream);
	while ((c = *src++)) {
		if (c == sq || c == bq)
			fputc(bq, stream);
		fputc(c, stream);
	}
	fputc(sq, stream);
}

void python_quote_print(FILE *stream, const char *src)
{
	const char sq = '\'';
	const char bq = '\\';
	const char nl = '\n';
	char c;

	fputc(sq, stream);
	while ((c = *src++)) {
		if (c == nl) {
			fputc(bq, stream);
			fputc('n', stream);
			continue;
		}
		if (c == sq || c == bq)
			fputc(bq, stream);
		fputc(c, stream);
	}
	fputc(sq, stream);
}

void tcl_quote_print(FILE *stream, const char *src)
{
	char c;

	fputc('"', stream);
	while ((c = *src++)) {
		switch (c) {
		case '[': case ']':
		case '{': case '}':
		case '$': case '\\': case '"':
			fputc('\\', stream);
		default:
			fputc(c, stream);
			break;
		case '\f':
			fputs("\\f", stream);
			break;
		case '\r':
			fputs("\\r", stream);
			break;
		case '\n':
			fputs("\\n", stream);
			break;
		case '\t':
			fputs("\\t", stream);
			break;
		case '\v':
			fputs("\\v", stream);
			break;
		}
	}
	fputc('"', stream);
}
Commit	Line	Data
6fb737be JH	1	#include "cache.h"
	2	#include "quote.h"
	3
5b8e6f85 DP	4	int quote_path_fully = 1;
5b8e6f85 DP	5
6fb737be	6	/* Help to copy the thing properly quoted for the shell safety.
77d604c3 PA	7	* any single quote is replaced with '\'', any exclamation point
77d604c3 PA	8	* is replaced with '\!', and the whole thing is enclosed in a
6fb737be JH	9	*
	10	* E.g.
	11	* original sq_quote result
	12	* name ==> name ==> 'name'
	13	* a b ==> a b ==> 'a b'
	14	* a'b ==> a'\''b ==> 'a'\''b'
77d604c3	15	* a!b ==> a'\!'b ==> 'a'\!'b'
6fb737be	16	*/
35eb2d36 LT	17	static inline int need_bs_quote(char c)
	18	{
	19	return (c == '\'' \|\| c == '!');
	20	}
	21
7a33bcbe	22	void sq_quote_buf(struct strbuf dst, const char src)
77d604c3	23	{
7a33bcbe PH	24	char *to_free = NULL;
	25
	26	if (dst->buf == src)
b315c5c0	27	to_free = strbuf_detach(dst, NULL);
7a33bcbe PH	28
	29	strbuf_addch(dst, '\'');
	30	while (*src) {
c2015b3a	31	size_t len = strcspn(src, "'!");
7a33bcbe PH	32	strbuf_add(dst, src, len);
	33	src += len;
	34	while (need_bs_quote(*src)) {
	35	strbuf_addstr(dst, "'\\");
	36	strbuf_addch(dst, *src++);
	37	strbuf_addch(dst, '\'');
6fb737be JH	38	}
6fb737be JH	39	}
7a33bcbe PH	40	strbuf_addch(dst, '\'');
7a33bcbe PH	41	free(to_free);
77d604c3 PA	42	}
77d604c3 PA	43
575ba9d6 ML	44	void sq_quote_print(FILE stream, const char src)
	45	{
	46	char c;
	47
	48	fputc('\'', stream);
	49	while ((c = *src++)) {
	50	if (need_bs_quote(c)) {
	51	fputs("'\\", stream);
	52	fputc(c, stream);
	53	fputc('\'', stream);
	54	} else {
	55	fputc(c, stream);
	56	}
	57	}
	58	fputc('\'', stream);
	59	}
	60
b319ce4c	61	void sq_quote_argv(struct strbuf dst, const char* argv, size_t maxlen)
7cf67205	62	{
7cf67205	63	int i;
7cf67205	64
7cf67205	65	/* Copy into destination buffer. */
b319ce4c CC	66	strbuf_grow(dst, 255);
b319ce4c CC	67	for (i = 0; argv[i]; ++i) {
7a33bcbe PH	68	strbuf_addch(dst, ' ');
	69	sq_quote_buf(dst, argv[i]);
	70	if (maxlen && dst->len > maxlen)
	71	die("Too many or long arguments");
7cf67205	72	}
86257aa3 CC	73	}
86257aa3 CC	74
ebbc088e	75	char sq_dequote_step(char arg, char **next)
35eb2d36 LT	76	{
	77	char *dst = arg;
	78	char *src = arg;
	79	char c;
	80
	81	if (*src != '\'')
	82	return NULL;
	83	for (;;) {
	84	c = *++src;
	85	if (!c)
	86	return NULL;
	87	if (c != '\'') {
	88	*dst++ = c;
	89	continue;
	90	}
	91	/* We stepped out of sq */
	92	switch (*++src) {
	93	case '\0':
	94	*dst = 0;
ebbc088e CC	95	if (next)
ebbc088e CC	96	*next = NULL;
35eb2d36 LT	97	return arg;
	98	case '\\':
	99	c = *++src;
	100	if (need_bs_quote(c) && *++src == '\'') {
	101	*dst++ = c;
	102	continue;
	103	}
	104	/* Fallthrough */
	105	default:
ebbc088e CC	106	if (!next \|\| !isspace(*src))
	107	return NULL;
	108	do {
	109	c = *++src;
	110	} while (isspace(c));
	111	*dst = 0;
	112	*next = src;
	113	return arg;
35eb2d36 LT	114	}
	115	}
	116	}
	117
ebbc088e CC	118	char sq_dequote(char arg)
	119	{
	120	return sq_dequote_step(arg, NULL);
	121	}
	122
663af342 PH	123	/* 1 means: quote as octal
	124	* 0 means: quote as octal if (quote_path_fully)
	125	* -1 means: never quote
	126	* c: quote as "\\c"
	127	*/
	128	#define X8(x) x, x, x, x, x, x, x, x
	129	#define X16(x) X8(x), X8(x)
	130	static signed char const sq_lookup[256] = {
	131	/* 0 1 2 3 4 5 6 7 */
	132	/* 0x00 */ 1, 1, 1, 1, 1, 1, 1, 'a',
	133	/* 0x08 */ 'b', 't', 'n', 'v', 'f', 'r', 1, 1,
	134	/* 0x10 */ X16(1),
	135	/* 0x20 */ -1, -1, '"', -1, -1, -1, -1, -1,
	136	/* 0x28 */ X16(-1), X16(-1), X16(-1),
	137	/* 0x58 */ -1, -1, -1, -1,'\\', -1, -1, -1,
	138	/* 0x60 */ X16(-1), X8(-1),
	139	/* 0x78 */ -1, -1, -1, -1, -1, -1, -1, 1,
	140	/* 0x80 / / set to 0 */
	141	};
	142
f3fa1838 JH	143	static inline int sq_must_quote(char c)
f3fa1838 JH	144	{
663af342 PH	145	return sq_lookup[(unsigned char)c] + quote_path_fully > 0;
	146	}
	147
	148	/* returns the longest prefix not needing a quote up to maxlen if positive.
	149	This stops at the first \0 because it's marked as a character needing an
	150	escape */
	151	static size_t next_quote_pos(const char *s, ssize_t maxlen)
	152	{
	153	size_t len;
	154	if (maxlen < 0) {
	155	for (len = 0; !sq_must_quote(s[len]); len++);
	156	} else {
	157	for (len = 0; len < maxlen && !sq_must_quote(s[len]); len++);
	158	}
	159	return len;
	160	}
	161
4f6fbcdc JH	162	/*
	163	* C-style name quoting.
	164	*
663af342 PH	165	* (1) if sb and fp are both NULL, inspect the input name and counts the
	166	* number of bytes that are needed to hold c_style quoted version of name,
	167	* counting the double quotes around it but not terminating NUL, and
	168	* returns it.
	169	* However, if name does not need c_style quoting, it returns 0.
4f6fbcdc	170	*
663af342 PH	171	* (2) if sb or fp are not NULL, it emits the c_style quoted version
	172	* of name, enclosed with double quotes if asked and needed only.
	173	* Return value is the same as in (1).
4f6fbcdc	174	*/
663af342 PH	175	static size_t quote_c_style_counted(const char *name, ssize_t maxlen,
663af342 PH	176	struct strbuf sb, FILE fp, int no_dq)
4f6fbcdc JH	177	{
4f6fbcdc JH	178	#undef EMIT
663af342 PH	179	#define EMIT(c) \
	180	do { \
	181	if (sb) strbuf_addch(sb, (c)); \
	182	if (fp) fputc((c), fp); \
	183	count++; \
	184	} while (0)
	185	#define EMITBUF(s, l) \
	186	do { \
	187	if (sb) strbuf_add(sb, (s), (l)); \
	188	if (fp) fwrite((s), (l), 1, fp); \
	189	count += (l); \
	190	} while (0)
	191
	192	size_t len, count = 0;
	193	const char *p = name;
4f6fbcdc	194
663af342 PH	195	for (;;) {
663af342 PH	196	int ch;
4f6fbcdc	197
663af342 PH	198	len = next_quote_pos(p, maxlen);
663af342 PH	199	if (len == maxlen \|\| !p[len])
50e7b067	200	break;
663af342 PH	201
	202	if (!no_dq && p == name)
	203	EMIT('"');
	204
	205	EMITBUF(p, len);
	206	EMIT('\\');
	207	p += len;
	208	ch = (unsigned char)*p++;
	209	if (sq_lookup[ch] >= ' ') {
	210	EMIT(sq_lookup[ch]);
	211	} else {
	212	EMIT(((ch >> 6) & 03) + '0');
	213	EMIT(((ch >> 3) & 07) + '0');
	214	EMIT(((ch >> 0) & 07) + '0');
4f6fbcdc	215	}
4f6fbcdc	216	}
663af342 PH	217
	218	EMITBUF(p, len);
	219	if (p == name) /* no ending quote needed */
	220	return 0;
	221
4f6fbcdc JH	222	if (!no_dq)
4f6fbcdc JH	223	EMIT('"');
663af342 PH	224	return count;
663af342 PH	225	}
4f6fbcdc	226
663af342 PH	227	size_t quote_c_style(const char name, struct strbuf sb, FILE *fp, int nodq)
	228	{
	229	return quote_c_style_counted(name, -1, sb, fp, nodq);
4f6fbcdc JH	230	}
4f6fbcdc JH	231
d5625091 JH	232	void quote_two_c_style(struct strbuf sb, const char prefix, const char *path, int nodq)
	233	{
	234	if (quote_c_style(prefix, NULL, NULL, 0) \|\|
	235	quote_c_style(path, NULL, NULL, 0)) {
	236	if (!nodq)
	237	strbuf_addch(sb, '"');
	238	quote_c_style(prefix, sb, NULL, 1);
	239	quote_c_style(path, sb, NULL, 1);
	240	if (!nodq)
	241	strbuf_addch(sb, '"');
	242	} else {
	243	strbuf_addstr(sb, prefix);
	244	strbuf_addstr(sb, path);
	245	}
	246	}
	247
663af342	248	void write_name_quoted(const char name, FILE fp, int terminator)
9ef2b3cb	249	{
663af342 PH	250	if (terminator) {
	251	quote_c_style(name, NULL, fp, 0);
	252	} else {
	253	fputs(name, fp);
	254	}
	255	fputc(terminator, fp);
	256	}
	257
	258	extern void write_name_quotedpfx(const char *pfx, size_t pfxlen,
	259	const char name, FILE fp, int terminator)
	260	{
	261	int needquote = 0;
	262
	263	if (terminator) {
	264	needquote = next_quote_pos(pfx, pfxlen) < pfxlen
	265	\|\| name[next_quote_pos(name, -1)];
	266	}
	267	if (needquote) {
	268	fputc('"', fp);
	269	quote_c_style_counted(pfx, pfxlen, NULL, fp, 1);
	270	quote_c_style(name, NULL, fp, 1);
	271	fputc('"', fp);
	272	} else {
	273	fwrite(pfx, pfxlen, 1, fp);
	274	fputs(name, fp);
	275	}
	276	fputc(terminator, fp);
9ef2b3cb JH	277	}
9ef2b3cb JH	278
a734d0b1 DP	279	/* quote path as relative to the given prefix */
	280	char quote_path_relative(const char in, int len,
	281	struct strbuf out, const char prefix)
	282	{
	283	int needquote;
	284
	285	if (len < 0)
	286	len = strlen(in);
	287
	288	/* "../" prefix itself does not need quoting, but "in" might. */
	289	needquote = next_quote_pos(in, len) < len;
	290	strbuf_setlen(out, 0);
	291	strbuf_grow(out, len);
	292
	293	if (needquote)
	294	strbuf_addch(out, '"');
	295	if (prefix) {
	296	int off = 0;
	297	while (prefix[off] && off < len && prefix[off] == in[off])
	298	if (prefix[off] == '/') {
	299	prefix += off + 1;
	300	in += off + 1;
	301	len -= off + 1;
	302	off = 0;
	303	} else
	304	off++;
	305
	306	for (; *prefix; prefix++)
	307	if (*prefix == '/')
	308	strbuf_addstr(out, "../");
	309	}
	310
	311	quote_c_style_counted (in, len, out, NULL, 1);
	312
	313	if (needquote)
	314	strbuf_addch(out, '"');
	315	if (!out->len)
	316	strbuf_addstr(out, "./");
	317
	318	return out->buf;
	319	}
	320
4f6fbcdc JH	321	/*
	322	* C-style name unquoting.
	323	*
7fb1011e PH	324	* Quoted should point at the opening double quote.
	325	* + Returns 0 if it was able to unquote the string properly, and appends the
	326	* result in the strbuf `sb'.
	327	* + Returns -1 in case of error, and doesn't touch the strbuf. Though note
	328	* that this function will allocate memory in the strbuf, so calling
	329	* strbuf_release is mandatory whichever result unquote_c_style returns.
	330	*
	331	* Updates endp pointer to point at one past the ending double quote if given.
4f6fbcdc	332	*/
7fb1011e	333	int unquote_c_style(struct strbuf sb, const char quoted, const char **endp)
4f6fbcdc	334	{
7fb1011e PH	335	size_t oldlen = sb->len, len;
7fb1011e PH	336	int ch, ac;
4f6fbcdc JH	337
4f6fbcdc JH	338	if (*quoted++ != '"')
7fb1011e PH	339	return -1;
	340
	341	for (;;) {
	342	len = strcspn(quoted, "\"\\");
	343	strbuf_add(sb, quoted, len);
	344	quoted += len;
4f6fbcdc	345
7fb1011e PH	346	switch (*quoted++) {
	347	case '"':
	348	if (endp)
c8744d6a	349	*endp = quoted;
7fb1011e PH	350	return 0;
	351	case '\\':
	352	break;
	353	default:
	354	goto error;
	355	}
	356
	357	switch ((ch = *quoted++)) {
	358	case 'a': ch = '\a'; break;
	359	case 'b': ch = '\b'; break;
	360	case 'f': ch = '\f'; break;
	361	case 'n': ch = '\n'; break;
	362	case 'r': ch = '\r'; break;
	363	case 't': ch = '\t'; break;
	364	case 'v': ch = '\v'; break;
	365
	366	case '\\': case '"':
	367	break; /* verbatim */
	368
	369	/* octal values with first digit over 4 overflow */
	370	case '0': case '1': case '2': case '3':
4f6fbcdc	371	ac = ((ch - '0') << 6);
7fb1011e PH	372	if ((ch = *quoted++) < '0' \|\| '7' < ch)
7fb1011e PH	373	goto error;
4f6fbcdc	374	ac \|= ((ch - '0') << 3);
7fb1011e PH	375	if ((ch = *quoted++) < '0' \|\| '7' < ch)
7fb1011e PH	376	goto error;
4f6fbcdc JH	377	ac \|= (ch - '0');
	378	ch = ac;
	379	break;
	380	default:
7fb1011e	381	goto error;
4f6fbcdc	382	}
7fb1011e	383	strbuf_addch(sb, ch);
4f6fbcdc JH	384	}
4f6fbcdc JH	385
7fb1011e PH	386	error:
	387	strbuf_setlen(sb, oldlen);
	388	return -1;
4f6fbcdc JH	389	}
4f6fbcdc JH	390
9f613ddd JH	391	/* quoting as a string literal for other languages */
	392
	393	void perl_quote_print(FILE stream, const char src)
	394	{
	395	const char sq = '\'';
	396	const char bq = '\\';
	397	char c;
	398
	399	fputc(sq, stream);
	400	while ((c = *src++)) {
	401	if (c == sq \|\| c == bq)
	402	fputc(bq, stream);
	403	fputc(c, stream);
	404	}
	405	fputc(sq, stream);
	406	}
	407
	408	void python_quote_print(FILE stream, const char src)
	409	{
	410	const char sq = '\'';
	411	const char bq = '\\';
	412	const char nl = '\n';
	413	char c;
	414
	415	fputc(sq, stream);
	416	while ((c = *src++)) {
	417	if (c == nl) {
	418	fputc(bq, stream);
	419	fputc('n', stream);
	420	continue;
	421	}
	422	if (c == sq \|\| c == bq)
	423	fputc(bq, stream);
	424	fputc(c, stream);
	425	}
	426	fputc(sq, stream);
	427	}
5558e55c SP	428
	429	void tcl_quote_print(FILE stream, const char src)
	430	{
	431	char c;
	432
	433	fputc('"', stream);
	434	while ((c = *src++)) {
	435	switch (c) {
	436	case '[': case ']':
	437	case '{': case '}':
	438	case '$': case '\\': case '"':
	439	fputc('\\', stream);
	440	default:
	441	fputc(c, stream);
	442	break;
	443	case '\f':
	444	fputs("\\f", stream);
	445	break;
	446	case '\r':
	447	fputs("\\r", stream);
	448	break;
	449	case '\n':
	450	fputs("\\n", stream);
	451	break;
	452	case '\t':
	453	fputs("\\t", stream);
	454	break;
	455	case '\v':
	456	fputs("\\v", stream);
	457	break;
	458	}
	459	}
	460	fputc('"', stream);
	461	}